Emergency alert data delivery apparatus and methods

ABSTRACT

Apparatus and methods for efficiently and flexibly providing emergency alert data (e.g., EAS messages) to subscribers of a content-based network, such as for example Internet protocol television (IPTV) subscribers. In one exemplary embodiment, the apparatus includes a server performing real-time receipt and encapsulation of the EAS data (which may comprise audio, video, and/or text), transport of the EAS data to client devices over the network, and use of one or more applications running on the client devices to decode and display/present the EAS data in a manner which effectively guarantees that it will be perceived by the viewer. In one variant, instant messaging (IM) infrastructure is used to authenticate clients and receive and display at least portion of the EAS data via a separate transport process. Server and client-side apparatus adapted for EAS data receipt, decoding and display are also disclosed.

RELATED APPLICATIONS

This application is related to co-pending U.S. patent application Ser.No. 11/298,247 filed contemporaneously herewith and entitled “CAPTIONDATA DELIVERY APPARATUS AND METHODS”, which is incorporated herein byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates generally to the field of delivery ofdigital media data (e.g., text, video, and/or audio) over networks suchas the Internet, and specifically in one aspect to delivering emergencyalert system (EAS) data in a broadcast “IPTV” network.

2. Description of Related Technology

Emergency Alert System (EAS)—

As is well known, the Emergency Alert System (EAS) is designed to allowfor the rapid and widespread dissemination of information relating to anational or local emergency to the general public. EAS messages aretransmitted for either national, state or local emergencies or otherevents. Examples of these emergencies or events include: severe weatherwatch/storm warning, flash floods, earthquakes/tsunami, and war or other“man made” emergencies.

The EAS was designed in part by the Federal Communications Commission(FCC) in cooperation with the National Weather Service (NWS) and theFederal Emergency Management Agency (FEMA), in order to support theroles of each organization. The FCC provides information tobroadcasters, cable system operators, and other participants in the EASregarding the technical and operational requirements of the EAS.Additionally, the FCC ensures that state and local EAS plans conform toFCC rules and regulations. The NWS provides emergency weatherinformation to alert the public about dangerous or potentiallyconditions weather conditions or other natural events. FEMA providesdirection for state and local emergency planning officials to plan andimplement their roles in the EAS.

Since Dec. 31, 1998, cable systems that have 10,000 or more subscribersare part of the EAS. These cable systems have the capability to transmitemergency messages on all of their video channels.

Alerts sent via the EAS may arrive in the form of text, audio and/orvideo content. Depending on the message type, the subscriber'stelevision or set-top box (STB) will display the message in theappropriate format and according to the prescribed method. State andLocal area emergency messages may be transmitted by using EAS Header andEnd of Message Codes. In television environments, the FCC recommendsthat the codes be preceded by an announcement that informs listenersthat an EAS transmission will occur.

In current digital and analog television systems, the EAS transmissionsare received from an over-the-air broadcast. The transmission is thenused in two different ways.

First, for analog broadcasts, all of the analog channels are eitherforce-tuned to a broadcast of the EAS transmission or create theappropriate overlay of text and audio. Nothing is required at thesubscriber (e.g., set-top box) side since all switching and displayfunctionality is performed in the network head-end.

Second, for digital broadcasts, the digital head-end application serverreceives the transmission and creates the proper audio, video and/ortext message for the digital set-top box (DSTB) or other consumerpremises equipment. The DSTB is then responsible for displaying themessage to the user as prescribed by the government mandate. If the EAStransmission is video, then the DSTB will “forcibly” tune its tuner tothe appropriate analog RF channel to receive, decode and display thevideo.

Testing of the EAS system generally comprises a weekly test consistingof an eight-second digital data signal. There is also a monthly testthat utilizes a test script (e.g., “This is a test of the EmergencyAlert System—this is only a test . . . ”). The monthly test script maybe developed locally and may contain information that is relevant to thelocal area into which it is being delivered.

Other features of the digital EAS systems include:

(i) Automatic Operation—The EAS digital system architecture allowsbroadcast stations, cable systems, participating satellite companies,and other services to send and receive emergency information quickly andautomatically even if those facilities are unattended;

(ii) Redundancy—The EAS requires monitoring of at least two independentsources for emergency information. This insures that emergencyinformation is received and delivered to viewers and listeners; and

(iii) Multi-language—EAS digital messages can be automatically convertedinto any language used by the broadcast station or cable system.

“IPTV” and other Network Paradigms—

Recently, network operators have begun using other types of networkssuch as Internet protocol (IP) networks to distribute broadcasttelevision programming to subscribers. This is to be contrasted withmore traditional radio frequency (over-the-air) broadcasts, or in-banddelivery via packetized MPEG-2 program streams. Such IP delivery ofbroadcast television programming also requires a method for the deliveryof EAS data to subscriber units such as personal computers (PC), as wellas a method to display such information on the display monitor (andaudio system) of these units.

In emerging Internet protocol television (IPTV) and similar distributionnetworks, a wider choice of audio/video codecs is being considered. Forexample, MPEG-2, MPEG-4/H.264 (advanced video codec or “AVC”), WindowsMedia Codec by Microsoft, and RealVideo by Real Networks are a few ofthe possible audio/video compression formats that have been deployed.While these new formats and their associated compression technology isuseful in providing streaming audio/video programs to end users, theseformats do not typically support any type of EAS data delivery. Whilesome video codecs have the ability to embed caption or similarinformation within the video stream (MPEG-2/MPEG-4, etc.), many videocodecs do not (e.g., RealVideo). Accordingly, the ability to transportat least some of the EAS information to the displaying client outside ofthe content (e.g., video) packet streams would be of particular utility.

Other Emergency Alert Approaches—

A variety of other approaches to emergency alert transmission over anetwork (and display be user devices) are evidenced in the prior art.For example, U.S. Pat. No. 3,993,955 to Belcher, et al. issued Nov. 23,1976 entitled “Method and apparatus for establishing emergencycommunications in a two-way cable television system” discloses a two-waycable television communications system wherein a central or masterstation is coupled to a plurality of remote stations through a coaxialcable network, each remote unit is provided with means for decoding anemergency alert transmission signal from the master station to generatean internal signal to sound an annunciator, alerting a subscriber orviewer at the remote station that an emergency communication isforthcoming, switching on a television receiver at the remote station,if the television receiver is not on, and tuning the television receiverthrough a converter to a predetermined television channel to conditionthe television receiver to receive emergency communications from themaster station.

U.S. Pat. No. 6,240,555 issued May 29, 2001 to Shoff, et al entitled“Interactive entertainment system for presenting supplementalinteractive content together with continuous video programs” disclosesan interactive entertainment system that enables presentation ofsupplemental interactive content along side traditional broadcast videoprograms. The programs are broadcast in a conventional manner. Thesupplemental content is supplied as part of the same program signal overthe broadcast network, or separately over another distribution network.A viewer computing unit is located at the viewer's home to present theprogram and supplemental content to a viewer. When the viewer tunes to aparticular channel, the viewer computing unit consults an electronicprogramming guide (EPG) to determine if the present program carried onthe channel is interactive. If it is, the viewer computing unit launchesa browser. The browser uses a target specification stored in the EPG toactivate a target resource containing the supplemental content forenhancing the broadcast program. The target resource contains displaylayout instructions prescribing how the supplemental content and thevideo content program are to appear in relation to one another whendisplayed. When the data from the target resource is downloaded, theviewer computing unit is responsive to the layout instructions obtainedfrom the target resource to display the supplemental contentconcurrently with the video content program. Embedding the layoutinstructions in the supplemental content places control of thepresentation to the content developers.

U.S. Pat. No. 6,452,492 to Drury issued on Sep. 17, 2002 entitled“Emergency alert system” discloses an alert system for providing analert of an actual or impending emergency to homes, businesses and thelike. The alert system is used in cable system network over whichcommunication signals are transmitted to a receiver remote from thetransmitter. Such communication signals have associated therewith atleast one distinguishable modulation frequency. The alert systemincludes a mechanism for receiving an alert request and a transmitterfor transmitting an alert signal in response to the alert request. Thetransmitter is coupled with the cable system and generates an alertsignal which is modulated at a frequency distinguishable from thefrequencies of the communication signals. The transmitter includes asideband filter to reduce the subharmonics generated around the alertsignal frequency. The receiver includes a mechanism for detecting avalid alert signal from the alert signal received and for generating analarm signal therefrom. The alert system also comprises an alarmindicator connected to the receiver providing an alarm upon receipt ofan alarm signal.

U.S. Pat. No. 6,714,534 to Gerszberg, et al. issued Mar. 30, 2004entitled “Lifeline service for HFCLA network using wireless ISD”discloses a system architecture for bypassing a local exchange carriercomprises an intelligent terminal, a residential gateway coupled to theterminal, a cable facility management platform terminating a twistedpair or coaxial cable facility and a network service platform. Thetwisted pair and/or coaxial cable fed, integrated residence gatewaycontrolled intelligent terminal or set-top device provides a pluralityof enhanced services. One necessary service is lifeline service that maybe provided over the coaxial cable via a cable modem of the integratedresidence gateway, over the twisted pair facility or via wireless means.The integrated residence gateway is coupled to either or both of thecoaxial cable or twisted pair and distributes the bandwidth facilitiesavailable over either service vehicle to customer devices including theset top box. Wireless lifeline or emergency services may be offeredthrough transceivers placed at the integrated residence gateways and/orat taps feeding the integrated residence gateways.

U.S. Pat. No. 6,766,163 issued Jul. 20, 2004 to Sharma entitled “Methodand system of displaying teletext information on mobile devices”discloses a communication system and method for communicating teletextinformation to mobile stations. A wireless access protocol (WAP) serveris coupled to a television station and receives a signal which includesteletext information from the station. The WAP server includes ateletext decoder which decodes the teletext information in thetransmitted signal. The decoded information is stored in memory using aserver controller. The controller receives information requests from anetwork interface coupled to the mobile stations. The controlleraccesses the teletext information stored in memory and transmits theinformation to the mobile station through the network interface.

U.S. Pat. No. 6,771,302 issued Aug. 3, 2004 to Nimri, et al entitled“Videoconference closed caption system and method” discloses a systemand method for closed caption in a videoconference environment. In amethod according to one embodiment of the invention, a connection isestablished with a videoconference device. Subsequently, a closedcaption page associated with the videoconference device is selected.Text is then entered on the closed caption page. The text is displayedto at least one device associated with a videoconference in which thevideoconference device is participating.

U.S. Pat. No. 6,792,616 issued Sep. 14, 2004 entitled “System and methodfor providing a plurality of programming services in a televisionsystem” discloses a system and method of providing for displaying a fullservice cable television system. The cable television system is adaptedto provide a plurality of different user services. Accordingly, thesystem and method are designed to allow a user to access services in anefficient memory conserving fashion. Using a plurality of data tables, acable television system is able to access a plurality of differentservices including cable channels, interactive program guides, pay perview activation, video on demand and interactive online services such asworld wide web browsing and E-mail via their home television set. Amechanism is provided whereby applications on a home device (HCT) can beactivated from the server via a signaling message received from the HCT,to provide the user with services such as Emergency Alert Messages,email, and other messaging.

U.S. Pat. No. 6,903,779 issued Jun. 7, 2005 to Dyer entitled “Method andsystem for displaying related components of a media stream that has beentransmitted over a computer network” discloses a system and method fordisplaying related components of a media stream that has beentransmitted over a computer network that includes at least one storagedevice that communicates with a television decoder and with the videodisplay. Information from one or more components of the media stream isextracted from the media stream and delivered to one or more storagedevices. This stored component is subsequently transmitted to the videodisplay in response to an information release signal that is embedded inthe information. The invention can be used to display closed caption andother information with associated audio and video signals using anaudio-visual media player.

United States Patent Application No. 20030121036 to Lock, et al.published on Jun. 26, 2003 entitled “CATV messaging alert system”discloses an invention that relates generally to use of standard videoscan lines of commercial television programming in a cable televisionsystem for transmitting alerting and other messaging information, to analert receiver unit at an end user's address. The alert receiver unitoperates completely independently of any television set at the enduser's address, other than to send the CATV signal from the alertreceiver unit to the television set. The subscriber or other user cansend certain pre-selected signals to the operator of the cable TVsystem, to another subscriber/user, or to another recipient designatedby the operator of the cable TV system. The invention relates toemergency notification systems and to systems for communicatingemergency messages to subscribers to cable television distributionnetworks, as well as to non-subscribers.

United States Patent Publication No. 20040181811 to Rakib published onSep. 16, 2004 entitled “Thin DOCSIS in-band management for interactiveHFC service delivery” discloses circuitry and process for transmittingvideo-on-demand and interactive service data and other service data onan MPEG multiplex and sending management and control data includingconditional access The management and control data can include requestedapplication software for download to the STBs, requested program guidedata, conditional access key data such as EMM messages, eventprovisioning data, emergency alert service data, and messages to manageand control the interactive and VOD services, and targeted advertising,etc.

United States Patent Publication No. 20050015799 to Park published Jan.20, 2005 entitled “Apparatus and method for displaying out-of-band (OOB)channel information in open cable system” discloses an apparatus and amethod for displaying out-of-band information without turning on a TV orset-top box in an open cable system. A receiving unit receives anout-of-band signal transmitted from a headend and parses the signal. Astorage unit stores the parsed data and a user's display setting. Aprocessing unit loads the user's display setting from the storage unitand processes the data according to the user's display setting. Acontrol unit further processes the processed data and causes the furtherprocessed data to be displayed on an auxiliary display or main display,wherein the auxiliary display displays the further processed data in astand-by mode state. The OOB signal may contain an electronic programguide (EPG), impulse-pay-per-view (IPPV), Data, an emergency alertsystem (EAS), video on demand (VOD), web, e-mail information and thelike.

United States Patent Publication No. 20050151639 to Bulmer publishedJul. 14, 2005 entitled “Alert System” discloses a system for alertingthe public regarding a criminal act; a plurality of law enforcementsmodes which generate alerts related to a criminal or emergency issue andtransmit the same to a central server; a central server system includingan administration workstation and database for receiving the alerts andcreating broadcast messages; and a broadcast system associated with thecentral server for broadcasting an alert via a televised broadcast,internet transmission or satellite transmission.

United States Patent Publication No. 20050162267 to Khandelwal, et al.published on Jul. 28, 2005 and entitled “Emergency alert service”discloses an emergency alert service that responds to receipt ofemergency alert messages by filtering, formatting and routing emergencyalert information to a variety of different networked appliances (andalso to remote devices). In this way, a consistent warning message isdisseminated simultaneously over many different warning systems, thusincreasing warning effectiveness while simplifying the warning task. Thesystem thus provides a common alerting protocol that is capable ofexchanging all-hazard emergency alerts and public warnings overdifferent kinds of networks.

United States Patent Publication No. 20050198684 to Stone, et al.published Sep. 8, 2005 entitled “Method and apparatus for providing aDSG to an OOB transcoder” discloses a method and apparatus for providinga DOCSIS Set-top Gateway (DSG) to OOB transcoder in a cable televisionsystem comprising a legacy set-top device. In the first embodiment, aone-way DSG to OOB transcoder acts as a proxy device for OOB messages tothe DSG tunnel. These OOB messages may include messages containingsystem information, emergency alert information, and conditional accessinformation. These set-top devices equipped with one or more DOCSIStuners are referred to as “DSG compatible” set-top devices. Once an OOBmessage is generated, the OOB message is transmitted to the DSG tunnel.The DSG to OOB transcoder of the present invention then captures the OOBmessage, and communicates the OOB message to the legacy set-top device.In a second embodiment of the invention, the legacy set-top device maycommunicate return communications to the DSG to OOB transcoder bygenerating a QPSK message. The QPSK message is then translated to an OOBmessage comprising DOCSIS content.

“Digicable” is another prior art system supplied by General Instrument(Motorola) for end-to-end satellite and cable system distributionnetworks. It uses an out-of-band data channel to deliver common systeminformation associated with all in-band channels. Out-of-band traffic inthese systems included: Entitlement Management Messages (EMM) addressedto individual STBs and carrying conditional access secure authorizationinstructions for requested services; Service Information that supportsthe STB navigation application with information about the requestedservice; program guide information to display what is on the variouschannels at various times; an Emergency Alert System messages to causethe STB to display a text message, play an audio message or force tuningto an alert channel.

From the foregoing, it is clear that while the prior art has generallyrecognized the need to receive and provide EAS data to client devicesover analog networks, and to enable EAS decode and display capabilitycompatible with an audio/video decoder on a client device, it fails toaddress several issues pertaining to IPTV deployments. For example, whenEAS data is embedded with packets belonging to a particular videoformat, decoders that wish to receive video in another format cannotmake use of this EAS data stream. This requires that the IPTV operatorrepeat EAS data for each different video format anticipated in thenetwork.

Moreover, the prior art fails to make effective use of the pervasiveconnectivity of an IP network to distribute various functions of EASdata reception, formatting, streaming, service authentication etc.across multiple servers located at different locations and communicatingwith each other over the IP network.

Accordingly, what is needed are apparatus and methods that provide amechanism for receiving multiple channels of baseband video in real-timefrom the content providers (typically received via satellite or somelocal origination source) while also providing for the capability toreceive and deliver emergency alert data in multiple forms (i.e., audio,video, and text data) to the end-user's client device application fordisplay and presentation. Such apparatus and methods should bepreferably deployable over a packet-switched network (such as an IPnetwork), such that subscribers can use the service by using commonlyavailable PC or similar software applications. They should also be ableto localize or regionalize the delivery of the EAS data (e.g., by zipcode or some other geographic metric), and substantially pre-empt atleast portions of ongoing programming so that the emergency alert datais clearly and unequivocally communicated to the targeted subscriberbase. Lastly, these methods and apparatus would require only minimalchanges to existing systems, thereby leveraging the installedinfrastructure as much as possible.

SUMMARY OF THE INVENTION

The present invention addresses the foregoing needs by providing, invarious embodiments, methods and apparatus for providing EAS data overnetworks such as IPTV networks.

In a first aspect of the invention, a system for distribution of bothmedia content and emergency alert information over a network isdisclosed. In one embodiment, the network comprises a packet-switchednetwork, and the system comprises: a content source adapted to generatemedia content; a receiver adapted to receive emergency alertinformation, the alert information comprising at least video and atleast one of audio or text; an emergency alert server in datacommunication with the receiver and adapted to generate alert datarelating to the alert information, the alert data comprising at leastone alert video stream; a video streaming server in data communicationwith the content source; and at least one client device in datacommunication with the streaming server and the alert server, the atleast one client device configured to receive at least the media contentfrom the streaming server and the emergency alert data from the alertserver, and display the alert data according to a prescribed protocol,the protocol including at least temporarily tuning the client device toreceive the at least one alert video stream.

In a second aspect of the invention, a method of delivering alert dataover a network is disclosed. In one embodiment, the network comprises apacket-switched network comprising at least one multimedia serverconfigured to send multimedia programs, at least one data serverdifferent from the multimedia server configured to send alert data, anda plurality of client devices in direct or indirect signal communicationwith the servers, an the method comprises: receiving the alert data fromone or more alert sources; formatting the alert data in a formatsuitable for transport over the network; delivering the alert data tothe one or more client devices over the network; and causing the clientdevices to: display at least a first portion of the alert data on adisplay device associated with respective ones of the client devices;and present an audio portion of the alert data in place of the audio ofat least one of the multimedia programs.

In a second embodiment, the method comprises: receiving the one or moreemergency alerts from the one or more alert broadcast sources;formatting the one or more alerts into the alert data having a formatsuitable for transport over the packet-switched network; delivering theone or more multimedia programs to the one or more client devices over afirst transport stream associated with a first process running on theone or more client devices; and delivering the alert data to the one ormore client devices over a second transport stream different from thefirst and associated with a second process running on the same ones ofthe one or more client devices on which the first process is running.

In a third aspect of the invention, consumer equipment adapted for usewithin an IPTV network is disclosed. In one embodiment, the equipmentcomprises: a multimedia content decoder and display unit; a computerprogram configured to receive and decode emergency alert data; acomputer program configured to display the decoded alert data; acomputer program configured to substantially preempt an audio portion ofa multimedia program stream being decoded and displayed on the consumerequipment; and a computer program configured to tune the consumerequipment to a second program stream containing emergency alert videocontent.

In a fourth aspect of the invention, network server apparatus for use ina network is disclosed. In one embodiment, the network comprises an IPTVbroadcast network having a plurality of client devices, and theapparatus comprises: a receiver unit configured to receive emergencyalert data from incoming broadcast signals; a formatting unit configuredto process the alert data to place it in a format suitable fortransmission over the IPTV network; and a delivery unit configured todeliver the alert data on the IPTV network to the client devices. In onevariant, the alert data comprises video, text, and audio alert data, andthe apparatus is further configured to selectively transmit video alertdata to subscribers of the IPTV network via a packet stream differentthan a packet stream carrying the audio and/or text alert data.

In a fifth aspect of the invention, apparatus capable of selectivelyproviding emergency alert data to a plurality of client devicesreceiving content transmitted over a packet-switched network isdisclosed. In one embodiment, the apparatus comprises: a processoradapted to run at least one computer program thereon, the processorfurther being adapted to access a storage device in data communicationwith the processor, the storage device storing a plurality of datarelating to individual ones of the plurality of client devices; and acomputer program running on the processor and adapted to selectivelycause transmission of the emergency alert data to groups of theplurality of client devices based at least in part on the plurality ofdata. In one variant, the alert data comprises video, text, and audioalert data, and the apparatus is further configured to selectivelytransmit video alert data to subscribers of the packet-switched networkvia a packet stream different than a packet stream carrying the audioand/or text alert data.

In a sixth aspect of the invention, a method of operating content-basednetwork is disclosed. In one embodiment, the network comprises at leastone server and a plurality of consumer premises equipment (CPE) indirect or indirect signal communication therewith, and the methodcomprises: providing emergency alert data services to a plurality ofsubscribers associated with respective ones of the plurality of CPE;causing each of the CPE to possess an identifying parameter; receivingemergency alert data to be delivered to one or more of the CPE; andselectively delivering the emergency alert data to the one or more CPE,the selective delivery based at least in part on the identifyingparameter. In one variant, the content-based network comprises an IPTVnetwork, the IPTV network being comprised of at least portions of an HFCcable or satellite network. An IP transport mechanism is provided, andthe direct or indirect communication comprises data communication via acable modem of an HFC network.

In a seventh aspect of the invention, a method of doing business in acontent-based network is disclosed. In one embodiment, the networkcomprises at least one server and a plurality of consumer premisesequipment (CPE) in direct or indirect signal communication therewith,and the method comprises: providing emergency alert data services to aplurality of subscribers associated with respective ones of theplurality of CPE; causing each of the CPE to possess an identifyingparameter; receiving emergency alert data to be delivered to one or moreof the CPE; delivering the emergency alert data to subscribers; andselectively providing related services to one or more of thesubscribers, the act of selectively providing being based at least inpart on the identifying parameter. In one variant, the related servicesare contextually related to at least one aspect of the content of thealert data, and the act of selectively providing is performed using anIP-based transport mechanism via the cable modem.

In an eighth aspect of the invention, a method of providing primarycontent, emergency-related secondary content, and contextually-relatedtertiary content to users of a content-based network is disclosed. Inone embodiment, the network comprises a server and a client device indata communication therewith, and the method comprises: delivering theprimary content to the client device; delivering the secondary contentto the client device; accessing a descriptive data file associated withthe secondary content in order to obtain descriptive data therefrom, thedescriptive data relating to at least one aspect of theemergency-related content; providing the descriptive data to aprocessing entity to identify contextually related tertiary content;transmitting the secondary and tertiary content to the consumer premisesdevice over a network; and selectively displaying the primary contentand at least one of the secondary and tertiary content on a displaydevice associated with the client device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram illustrating an exemplarycontent-based (e.g., cable) network configuration useful with thepresent invention.

FIG. 1 a is a functional block diagram illustrating one exemplary HFCcable network head-end configuration useful with the present invention.

FIG. 2 is a functional block diagram illustrating one exemplarypacket-switched distribution network that useful with the presentinvention.

FIG. 2 a is a functional block diagram illustrating an exemplary networkEAS server device according to the invention.

FIG. 2 b is a functional block diagram illustrating an exemplary clientdevice adapted for EAS data receipt and display, according to theinvention.

FIG. 3 is a logical flowchart illustrating one embodiment of the methodof EAS data localization according to the invention.

FIG. 4 is graphic representation of an exemplary message exchangeprotocol showing messages exchanged between various elements of the EASdata processing and delivery system of FIG. 2.

FIG. 5 is a functional block representation of an exemplary IPTV networkwherein EAS data distribution utilizes an instant messaginginfrastructure.

FIG. 5 a is graphic representation of an exemplaryauthentication/identification message exchange protocol showing messagesexchanged between various elements of the IM infrastructure of FIG. 5.

FIG. 6 illustrates one exemplary embodiment of a client device (e.g.,PC) protocol stack illustrating the placement of the EAS client (e.g.,messenger application) of the present invention therein.

DETAILED DESCRIPTION OF THE INVENTION

Reference is now made to the drawings wherein like numerals refer tolike parts throughout.

As used herein, the terms “MSO” or “multiple systems operator” refer toa cable, satellite, or terrestrial network provider havinginfrastructure required to deliver services including programming anddata over those mediums.

As used herein, the terms “network” and “bearer network” refer generallyto any type of telecommunications or data network including, withoutlimitation, hybrid fiber coax (HFC) networks, satellite networks, telconetworks, and data networks (including MANs, WANs, LANs, WLANs,internets, and intranets). Such networks or portions thereof may utilizeany one or more different topologies (e.g., ring, bus, star, loop,etc.), transmission media (e.g., wired/RF cable, RF wireless, millimeterwave, optical, etc.) and/or communications or networking protocols(e.g., SONET, DOCSIS, IEEE Std. 802.3, ATM, X.25, Frame Relay, 3GPP,3GPP2, WAP, TCP/IP, SIP, UDP, FTP, RTP/RTCP, H.323, etc.).

As used herein, the term “head-end” refers generally to a networkedsystem controlled by an operator (e.g., an MSO) that distributesprogramming to MSO clientele using client devices. Such programming mayinclude literally any information source/receiver including, inter alia,free-to-air TV channels, pay TV channels, interactive TV, and theInternet. DSTBs may literally take on any configuration, and can beretail devices meaning that consumers may or may not obtain their DSTBsfrom the MSO exclusively. Accordingly, it is anticipated that MSOnetworks may have client devices from multiple vendors, and these clientdevices will have widely varying hardware capabilities. Multipleregional head-ends may be in the same or different cities.

As used herein, the terms “client device” and “end user device” include,but are not limited to, personal computers (PCs) and minicomputers,whether desktop, laptop, or otherwise, set-top boxes such as theMotorola DCT2XXX/5XXX and Scientific Atlanta Explorer2XXX/3XXX/4XXX/6XXX/8XXX series digital devices, personal digitalassistants (PDAs) such as the “Palm®” family of devices, handheldcomputers, personal communicators such as the Motorola Accompli or V710,J2ME equipped devices, cellular telephones, wireless nodes, or literallyany other device capable of interchanging data with a network.

Similarly, the terms “Customer Premises Equipment (CPE)” and “hostdevice” refer to any type of electronic equipment located within acustomer's or user's premises and connected to a network. The term “hostdevice” refers generally to a terminal device that has access to digitaltelevision content via a satellite, cable, or terrestrial network. Thehost device functionality may be integrated into a digital television(DTV) set. The term “customer premises equipment” (CPE) includes suchelectronic equipment such as set-top boxes, televisions, Digital VideoRecorders (DVR), gateway storage devices (Furnace), and ITV PersonalComputers.

As used herein, the term “network agent” refers to any network entity(whether software, firmware, and/or hardware based) adapted to performone or more specific purposes. For example, a network agent may comprisea computer program running in server belonging to a network operator,which is in communication with one or more processes on a CPE or otherdevice.

As used herein, the term “application” refers generally to a unit ofexecutable software that implements a certain functionality or theme.The themes of applications vary broadly across any number of disciplinesand functions (such as on-demand content management, e-commercetransactions, brokerage transactions, home entertainment, calculatoretc.), and one application may have more than one theme. The unit ofexecutable software generally runs in a predetermined environment; forexample, the unit could comprise a downloadable Java Xlet™ that runswithin the JavaTV™ environment.

As used herein, the term “computer program” is meant to include anysequence or human or machine cognizable steps which perform a function.Such program may be rendered in virtually any programming language orenvironment including, for example, C/C++, Fortran, COBOL, PASCAL,assembly language, markup languages (e.g., HTML, SGML, XML, VoXML), andthe like, as well as object-oriented environments such as the CommonObject Request Broker Architecture (CORBA), Java™ (including J2ME, JavaBeans, etc.) and the like.

The term “component” in the context of software refers generally to aunit or portion of executable software that is based on a related set offunctionalities. For example, a component could be a single class inJava™ or C++. Similarly, the term “module” refers generally to a looselycoupled yet functionally related set of components.

As used herein, the term “server” refers to any computerized component,system or entity regardless of form which is adapted to provide data,files, applications, content, or other services to one or more otherdevices or entities on a computer network.

As used herein, the terms “emergency alert system (EAS)”, “alert data”,“emergency alert (EA)”, and “emergency broadcast system” refer to,without limitation, the generation and/or delivery of text, audio,and/or visual or video information relating to events, alerts oremergency situations.

As used herein, the terms “closed captioning” “caption data” or “CCdata” are used to refer to, without limitation, the transcription ofaudio programs, as well as extended data services and VBI data/testsignals, and delivering information such as metadata associated with atelevision program (including inter alia providing URLs for selectiveadvertising, Really Simple Syndication (RSS) feed information related tovideo programs, news clips, stock, weather data, etc.

As used herein, the term “DOCSIS” refers to any of the existing orplanned variants of the Data Over Cable Services InterfaceSpecification, including for example DOCSIS versions 1.0, 1.1 and 2.0.DOCSIS (version 1.0) is a standard and protocol for internet accessusing a “digital” cable network. DOCSIS 1.1 is interoperable with DOCSIS1.0, and has data rate and latency guarantees (VoIP), as well asimproved security compared to DOCSIS 1.0. DOCSIS 2.0 is interoperablewith 1.0 and 1.1, yet provides a wider upstream band (6.4 MHz), as wellas new modulation formats including TDMA and CDMA. It also providessymmetric services (30 Mbps upstream).

Overview

In one aspect of the invention, methods and apparatus for receiving,transmitting and displaying emergency alert system (EAS) data (audio,video, and/or text) in a network environment are disclosed. In anexemplary embodiment, the network environment comprises an InternetProtocol Television (IPTV) System, and/or system for televisionbroadcast over a broadband connection. The data from an incoming EASfeed is passed to an EAS server for formatting and optional localization(targeting based on geography or other parameters). If the data is audioand/or text, then it is formatted into a message to be sent over the IPnetwork. The message is then received by the client device(s), which maycomprise for example an IP-enable DSTB, or a personal computer,including their EAS client application.

Once the EAS client receives the message, it is then displayed in a newwindow and/or overlay of the current video stream being displayed. Also,the EAS client generates an audio transmission based on the received EASmessage that will pre-empt the audio track of the current programstream. The text and audio can be repeated as many times as mandated bygovernment regulation, or based on another criterion. Advantageously, inthe exemplary embodiment, any device connected to the network that isviewing any program stream will receive the EAS message. In alternateembodiments (e.g., those using an Instant Messenger or comparabledelivery method for the EAS data), the EAS data will be independent ofthe program stream.

In the event that the EAS feed includes video content, the system also“force-tunes” the EAS client application via a message sent from e.g.,the EAS server. The message sent instructs the client video player totune to an appropriate broadcast, unicast, or multicast IP video streamto display the EAS video on the client device. The player displays theforce-tuned EAS stream until the EAS transmission has ended, at whichpoint the video client will then re-establish the display of thepreviously tuned IP video stream.

The invention overcomes the deficiencies in the prior art relating tothe lack of EAS decoding and display capability in the video decoderprograms of typical client devices (e.g., PCs).

The invention also advantageously provides for reuse of existingequipment intended for delivery of content over the packet-switchednetwork for emergency alert functions. In this fashion, no newinfrastructure or significant upgrades are required to implement theinvention. Exemplary embodiments of the invention comprise a clientsoftware stack that can function both with legacy IPTV video decoderapplications and legacy IM infrastructure, or alternatively as anintegrated application that performs video decoder plusclosed-captioning plus emergency alert display and presentationfunctions. However, literally any type of internet/network messaging canbe used as the basis for sending EAS-related content or messages.

The invention also provides strong authentication, using for example theDOCSIS infrastructure of the parent HFC network. Since the networkoperator controls both ingress point (e.g., the CMTS) of the EAS data,as well as the egress point (e.g., cable modem), appropriate securitymeasures such as firewalls and DOCSIS traffic-based security can betaken to prevent “hijacking”, hacking or other surreptitious activitiesaimed at corrupting or misusing the data or communication channel(s).

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Exemplary embodiments of the apparatus and methods of the presentinvention are now described in detail. While these exemplary embodimentsare described in the context of the previously mentioned DOCSIS hybridfiber coax (HFC) cable architecture, the general principles andadvantages of the invention may be extended to other types of networksand architectures where delivery of captioned information or data isrequired or desirable. Such other networks or architectures may bebroadband, narrowband, wired or wireless, content or data, or otherwise.Hence, the following description is merely exemplary in nature. Forexample, the invention may be practiced over a fiber-to-the-home (FTTH)or fiber-to-the-curb (FTTC) system or over future satellite ormillimeter wave-based network having two-way capabilities similar totoday's digital cable HFC networks.

It will also be appreciated that while described generally in thecontext of a network providing service to a customer or consumer (i.e.,residential) end user domain, the present invention may be readilyadapted to other types of environments including, e.g.,commercial/enterprise, and government/military applications. Myriadother applications are possible.

Network-Side Architecture—

Referring now to FIG. 1, an exemplary data-over-cable (DOCSIS) network100, including broadcast IPTV service, is shown. For clarity ofillustration, some details of the network not pertinent to the presentinvention have been omitted from FIG. 1. A “master” head-end 102 isconnected with one or more local nodes 104 via a network 100. Thenetwork 100 could for example comprise an optical fiber network of thetype known in the art using dense wave-division multiplexing (DWDM),Synchronous Optical Network (SONET) transport technology or gigabitEthernet transport. In the downstream direction (from the head-endservers or nodes to the CPE 106), this network performs the function ofcarrying digital and analog television signals as well as packetizeddata (e.g., IP) traffic. A cable modem termination system (CMTS) 110located at a local node 104 provides connectivity to the CPE 106 via thecoaxial drop 108. The CMTS interfaces 110 in turn are connected directlyor indirectly to the Internet or IP backbone, thereby providing accessfor the CPE 106 to the Internet (or other internets, intranets, ornetworks) via the cable network infrastructure. Aggregation oftelevision programs that include local and regional programming, orother types of content, occurs at the head-end 102, where these programsare converted into a suitable transport format and a “channel line-up”is created for delivery to the downstream CPE 106.

Referring now to FIG. 1 a, one exemplary embodiment of a head-endarchitecture useful with the present invention is described. As shown inFIG. 1 a, the head-end architecture 150 comprises typical head-endcomponents and services including billing module 152, subscribermanagement system (SMS) and CPE configuration management module 154, andOOB system 156, as well as LAN(s) 158, 160 placing the variouscomponents in data communication with one another. It will beappreciated that while a bar or bus LAN topology is illustrated, anynumber of other arrangements as previously referenced (e.g., ring, star,etc.) may be used consistent with the invention. The head-endarchitecture 150 may also include a cable-modem termination system(CMTS) if desired.

It will also be appreciated that the head-end configuration depicted inFIG. 1 a is high-level, conceptual architecture and that each MSO mayhave multiple head-ends deployed using custom architectures.

The architecture 150 of FIG. 1 a further includes amultiplexer/encrypter/modulator (MEM) 162 coupled to the HFC network 101adapted to “condition” content for transmission over the network. Thedistribution servers 104 are coupled to the LAN 160, which providesaccess to the MEM 162 and network 101 via one or more file servers 170.The VOD servers 105 are coupled to the LAN 160 as well, although otherarchitectures may be employed (such as for example where the VOD serversare associated with a core switching device such as an 802.3z GigabitEthernet device). As previously described, information is carried acrossmultiple channels. Thus, the head-end must be adapted to acquire theinformation for the carried channels from various sources. Typically,the channels being delivered from the head-end 150 to the CPE 106(“downstream”) are multiplexed together in the head-end and sent toneighborhood hubs (FIG. 1 b) via a variety of interposed networkcomponents.

Content (e.g., audio, video, etc.) is provided in each downstream(in-band) channel associated with the relevant service group. Tocommunicate with the head-end or intermediary node (e.g., hub server),the CPE 106 may use the out-of-band (OOB) or DOCSIS channels andassociated protocols. The OCAP 1.0 (and subsequent) specificationprovides for exemplary networking protocols both downstream andupstream, although the invention is in no way limited to these exemplaryapproaches.

Referring now to FIG. 2, an exemplary configuration of a packet-switchednetwork useful with the present invention is illustrated. Whiledescribed in the context of an Internet Protocol Television (IPTV)network, it will be recognized that the principles of the invention canbe extended to other transport modalities and network paradigms.

The network 200 of FIG. 2 effectively operates logically “along side”the in-band content delivery system described with respect to FIG. 1 a,and shares many common elements. It includes digital satellite receivers202, analog satellite receivers 204 and off-air receivers 206 deployedwithin the cable network in order to receive content such as broadcasttelevision programs. This content is then distributed over the cablenetwork. With respect to the IPTV network, the digital satellite feedreceived via the receiver 202 is sent to a video multiplexer 210 thatprovides one or more digital programs to one or more video encoders 218to transcode/transrate or otherwise process incoming digital videostreams to a format suitable for loading onto the video streaming server222.

An Emergency Alert Service (EAS) head-end server subsystem 214 is shownto operate in conjunction with the in-band and IPTV content systemsdescribed above. This subsystem includes a receiver 230 responsible forreceiving emergency alert messages from message feeds (e.g., in the formof RF communications on government designated disaster message broadcastfrequencies), or by other means. The messages or data thus received areconverted into a digital data format suitable for transmission over theIPTV network using a formatting unit 232. The formatting unit 232 alsooptionally regionalizes or localizes the data to allow for “targeted”delivery as discussed in greater detail subsequently herein. Note thatin FIG. 2, while localization and formatting are shown as a singlelogical functional block, actual implementations of these functions maybe on separate (and even disparate) platforms.

The subsystem 214 also contains one or more servers 234 that operate inconjunction with other servers in the network, in a manner describedfurther herein, in order to transmit emergency messages/content to theclient devices 220 over the interposed IP distribution network 216.

The video streaming server 222 and the EAS message server 234 are inturn connected to the IP Distribution Network 216 (which in the contextof a cable network, may comprise, inter alia, the coaxial “drop” 108 ofFIG. 1 between the CPE 106 and CMTS 110). Other architectural elementsconnected to the IP distribution network 216 are shown as “other relatedservers” 224 in FIG. 2. Client devices 220 (such as PCs connected tocable modems) are connected to the IP distribution network and performthe functions of, inter alia, decoding and displaying video and EASsignals.

It will be appreciated that several different embodiments of theabove-described IPTV network are possible consistent with the presentinvention. For example, the video encoders 218 shown in FIG. 2 may beconfigured to produce one or more bit streams for the same content. Suchbit streams could have different bit rates as a function of suitabilityfor transmission over the IP network (e.g., low, medium and high bitratestreams for dial-up, DSL and cable modem IP networks), and/or differentencoding formats conforming to audio/video encoding standards such asReal or MPEG or Windows Media Player (WMP). Similarly, the EAS head-endserver subsystem 214 could serve the emergency messages or content tothe client devices in unicast, multicast or broadcast manner.

It is noted that while localization of emergency messages or video is ahighly desired feature, this feature may be omitted or obviated incertain applications, such as when all client devices that a givenhead-end is serving are in the same emergency alert area. Also, theplacement of the localization function within the network can be varied;i.e., either (i) only at the head-end 150, (ii) partly at the head-endand partly at the client devices 220, or (iii) exclusively at the clientdevices 220.

Furthermore, the emergency alert data received by the network aretypically made available by governmental agencies by broadcasting themat pre-designated frequency over the air. In some implementations ofcontent distribution networks, these messages may be received in onelocation within the network, and carried over another medium (e.g.,fiber optic transmission) to other head-ends or nodes of the network. Insuch embodiments, the EAS receiver 230 may not contain an explicitover-the-air receiver, but still receive such messages.

Emergency Alert Service Subsystem—

Referring now to FIG. 2 a, one embodiment of the emergency alertsubsystem 214 (comprising a network EAS server device 234 with EASreceiver and formatting unit 232) according to the present invention isdescribed. As shown in FIG. 2 a, the exemplary server subsystem 214generally comprises an IP-based server module including a digitalprocessor(s) 253, RAM 255, mass storage device 256, and a plurality ofinterfaces 257 for connection with other network apparatus such as LANs,the local service node hardware, IP routers and other packet networkdevices, network management and provisioning systems, local PCs, etc.Other components which may be utilized within the server subsystem 214(depending on where it is employed and how it is physically implemented)include RF or satellite receivers (for receiving the EAS data feed fromthe source), encoders/decoders, encryption/decryption and/or errorcorrection algorithms, board level electronic components, as well asmedia processors and other specialized SoC or ASIC devices. Support forvarious processing layers and protocols (e.g., 802.3, SNMP, UDP, SNMP,H.323/RTP/RTCP, VoIP, SIP, etc.) may also be provided as required. Theserver subsystem 214 may also include a metadata “packager”, such as forpackaging extracted EAS data in an XML or other comparable format withina metadata file as discussed subsequently herein.

The server 214 of FIG. 2 a may take any number of physical forms,comprising for example one of a plurality of discrete modules or cardswithin a head-end component of the type well known in the art. Theserver may also comprise firmware, either alone or in combination withother hardware/software components such as those previously described.Alternatively, the server module 214 may be a stand-alone devicedisposed at the head-end, a hub, or other location. The server device214 may also be integrated with other types of components (such as videotransceivers, encoders/decoders, etc.) and form factors if desired.

It will be appreciated that while described in the context of separateserver disposed at the head-end 150 of the network as shown in FIG. 2,the EAS subsystem 214 may be adapted for use at other locations withinthe network. Furthermore, the receiver, formatting, and server functions230, 232, 234 may comprise a distributed software and/or hardwarearchitecture, such as where the aforementioned functions comprise two ormore portions of a distributed application (DA) in communication withone another yet running on different physical devices. Many suchpermutations and alternate configurations will be recognized by those ofordinary skill given the present disclosure.

Server/Client Interaction—

In conventional broadcast television systems, EAS alert information istypically viewed in a non-discretionary fashion. That is, theinformation typically will preempt at least portions of both the videoand audio portions of a given program.

While the present invention can be implemented in the context of theone-way or “broadcast” model as described above by delivering EAS datairrespective of the program or content the targeted subscribers are eachviewing, it also optionally makes advantageous use of the availabilityof two-way communication in an IPTV network. Interaction between clientdevices (e.g., PCs) and EAS servers in such a network can be furtherused for various ancillary or related functions including, inter alia,enforcement of service classes (by verifying whether a user is entitledto receive certain premium or advanced functions), profiling of theclient device 220 to advise the EAS servers of the client devicecapabilities, providing the appropriate EAS data to a client device (theright bitrate and format), and so forth.

Client/server interaction may also be performed pursuant to verifyingthe authenticity (i.e., authentication or identification) of a clientdevice/EAS software process or its user, or alternatively an EAS server.This approach frustrates surreptitious attempts to either “spoof” theclient devices via a false EAS server, or engage the EAS server in afalse message exchange (and delivery of EAS data content) by using aspoofed client device. Furthermore, while EAS transmissions are mandatedby Federal Government regulations in the United States, other type ofdata may be delivered that a service provider may only be made availableto subscribers of a particular service tier or group, as subsequentlydescribed herein

The client/server relationship may also be used for purposes ofredundancy; e.g., where the client device 220 is alerted to an incomingEAS message, yet does not receive it, or cannot successfully negotiatefor delivery of the EAS message, and hence must be re-directed to asecond or alternate server.

Client-Side Architecture—

Referring now to FIG. 2 b, one exemplary embodiment of the client device220 of FIG. 2 is described in detail. A client device 220 in the contextof the present invention generally comprises a personal computer (PC) orsimilar computerized device running, e.g., a Linux™ or Windows®operating system. As is well known, the client device 220 includes acomputer processor 270, mass storage 272, RAM 274, input device 276,display device 278, and communications interfaces 280 including forexample an RJ-45 LAN connector with Ethernet LAN card, USB ports,IEEE-1394 “Firewire” interface, wireless interface (such as 802.11 LANcard, WiMAX 802.16 interface, 802.15 PAN interface, or Bluetoothinterface), and so forth. Computerized systems (whether stationary ormobile) are well known to those of ordinary skill and accordingly notdescribed further herein.

The client device 220 (which may also be integrated, or in communicationwith, the CPE 106 of FIG. 1) may also include an external or internalmodem to achieve connectivity to the network. For example, it iscustomary to connect the Ethernet port of a PC to an Ethernet output ofa cable modem (CM) that itself is connected to a coaxial cable (e.g.,DOCSIS) data network. The PC in this case is logically connected to thenetwork side servers via an IP logical (and physical) channelestablished though the cable modem. In many existing personal computersconnected to IP networks, an audio/video decoder (such as the ubiquitousWindows Media Player, Apple QuickTime™ or Real Video) is readilyavailable on the client device, or easily downloaded thereto. However,such decoders lack support to display EAS message data obtained from anIP stream different than the video stream.

As discussed subsequently herein, another application ubiquitouslyavailable on such client platforms is an “Instant Messenger” programsuch as the America Online (AOL) Instant Messenger (AIM) or Yahoo!Messenger or MSN Messenger. The construction and operation of theseapplications are well known to those of ordinary skill, and accordinglynot described further herein.

In an exemplary embodiment of the present invention, a dedicated EASclient application is implemented to receive/decode/display both videoEAS data (e.g., video delivered over a packet stream flow via thestreaming server) and the EAS audio/text data (delivered by the EASserver subsystem 214). In another exemplary embodiment, the client-sideimplementation makes use of existing decoder software (e.g., Realdecoder) and an IM client program to display EAS video and presentaudio/text data, respectively. In yet another variation, the previousembodiment is further extended by using the IM client software and acorresponding IM server to authenticate a user.

Popular audio/video client software programs such as Windows MediaPlayer™, Apple QuickTime™ or Real™ Video cannot receive and displayEmergency Alert messages. As discussed in greater detail elsewhereherein, the present invention envisions client-side implementations thateither complement such widely available video clients by providing asecondary application that runs in conjunction with the video decoders,or a more client unitary application program that implements both videodecoder and emergency alert audio/text presentation functions (andoptionally instant messaging or IM functionality). Accordingly, the term“EAS client process” and the like encompasses all implementationsranging from discrete software components through a fully integratedsolution.

The EAS client 400 of the exemplary embodiment is also configured toswitch the client device back to its original program stream (ifswitched away) and cease the EAS audio data insertion, as well asremoving the display text window or overlay. Therefore, as soon as thefederal or other requirements for display have been met, the system canadvantageously “return to normal” in a seamless fashion withoutrequiring subscriber retuning or intervention. The automatic retuningcan be locally initiated (e.g., by the EAS client process 400 invoking are-tune event based on, for example, expiration of a timer variable), oralternatively via remote messaging (e.g., from the EAS server to theclient process 400 indicating that the EAS alert is complete). Myraidother mechanisms for reverting the client device (and video player) totheir original or pre-alert state will be recognized by those ofordinary skill given the present disclosure, and hence are not describedfurther herein.

Localization of Emergency Alert Messages—

Localization refers to “editing” the emergency alert messages or datareceived by the network operator such that the appropriate subset ofclient devices to whom the message may be applicable is able to receiveand decode it, while other client devices are able to discern that theemergency alert message is not targeted for them. For example, theemergency alert message specification for cable broadcast (ANSI standardJ-STD-042-2002, incorporated herein by reference in its entirety)describes localization in the form of county code and subdivision.

In an IPTV deployment such as one implemented over a cable data network,the locations of modems to which EAS clients are attached is availableat a network-side server. This may comprise, for example, a MAC addressor device ID associated with a given cable modem. Furthermore, “ranging”information may be used to validate an installation of a premisesdevice, based on expected signal propagation delays (thereby telling thenetwork operator when the device has been moved to another locationwithin the network). Such information can be taken advantage of whenformatting the EAS messages for targeting a specific subset of clientdevices. Hence, the present invention affords significant capability interms of tailoring the delivery of EAS messages to particular groups ofsubscribers. For example, the MSO may maintain a database of cable modemdevice IDs or MAC addresses and a corresponding postal zip code for eachsuch modem. When an tornado alert message is issued by NWS for certaincounties or zip codes, the MSO can rapidly access this database todetermine which device IDs/MAC addresses to which to route the EASmessage. Certain zip codes may merit a first type of message (e.g.,critical warning) while others may merit a less dire alert.

It will be appreciated that information other than zip code can be usedas well (or in conjunction) as a basis for differentiating messagedelivery and/or content, such as e.g., subscriber latitude/longitude,street address, elevation above sea level, etc. For example,commercially available software packages are capable of mapping givenstreet addresses to an elevation map, earthquake/fault/liquefaction map,etc. Hence, the MSO could feasibly pre-store such information for eachdevice ID/MAC address, and hence tailor the alert warnings for a heavyrain storm primarily to low-lying areas. Myriad other such “tailoring”approaches are possible according to the present invention.

FIG. 3 illustrates an exemplary method of performing client localizationfor EAS data delivery according to the invention. As shown, the firststep 302 of the method 300 comprises registering new network (e.g.,IPTV) clients within the database. This registration can include zipcode or other such relevant information as previously described, whichallows for targeted delivery of EAS data to selected subscribers.

Next, the EAS subsystem 214 receives the EAS feed information, such asthat relating to a natural disaster (step 304). The localization andformatting unit 232 of the server system 214 then performs localizationusing the information present in the client database per step 306. Thislocalization may comprise for example specifying the MAC addresses orDevice ID values for each of the cable modems associated with thetargeted subscriber base.

Lastly, per step 308, the localization data is used to transmit (e.g.,broadcast, unicast, or multicast) the relevant EAS data to the targetedclient devices 220 from the server subsystem 214.

Authentication of Emergency Alert Messages—

The intended end effect of an emergency alert message on a client deviceis disruptive to the viewing of audio/video program by the user (i.e.,“forced” viewing/hearing of the alert message in whatever form it isdelivered). Accordingly, when invoked, the EAS delivery system willpreempt (or at very least significantly detract from) all othermodalities of content delivery. It is therefore critical to provide amethod and apparatus that is robust, such that any unauthorized use ofthe emergency alert subsystem is: (i) prevented from occurring, and (ii)readily detected and defeated in case the methods of preventing suchsurreptitious access are somehow bypassed. Such security methods becomeeven more critical when the EAS client application running on the clientdevice is able to force a re-tuning of the client device to theemergency alert video stream/feed.

FIG. 4 is a signal exchange diagram highlighting two exemplaryembodiments of the present invention wherein the emergency alertmessages received by the client devices are explicitly validated bycommunication between the client device 220 (as represented by the EASprocess 400) and a head-end server process 402 (or alternatively the EASserver process 404).

FIG. 4 shows an emergency alert message transmission 414 by the EASserver process 404 to the client device 220 (and its EAS process 400). Arequest/response pair of messages 416, 418 are also shown, wherein uponreception of the EA message 414, the EAS client 400 requests itsauthentication from a head-end server process 402. In variousembodiments of the invention, the head-end server may comprise forexample a digital certificate authority (CA) server, a networkmanagement server associated with a cable modem network, or yet anothertype of server entity adapted for authentication and/or identificationfunctions.

In an alternate embodiment of the request/response authenticationprocess, message exchanges 420, 422 can be used as shown in FIG. 4. Inthis exchange, the EAS client 400 sends a confirmation request back tothe EAS server process 404 at the IP address known to the client toverify that the EAS message was indeed sent by the EAS server process.

Various other embodiments of the message exchange/authentication processare possible according to the invention. These include, but not limitedto, use of an encrypted data transmission (e.g., using secure HTTPtransmission), and data hashing techniques based on keys. Some datanetworks may also include a “firewall” or other comparable softwaremechanism that filters messages arriving from outside the network on TCPor UDP ports specifically assigned to EAS messages. Myriad otherapproaches and combinations will be recognized by those of ordinaryskill when provided the present disclosure.

Instant Messaging Variants—

In one exemplary embodiment of the invention, alert data is provided tothe client devices 220 (and the EAS client process 440) by using instantmessaging (IM) technology and using IM servers available in the IPnetwork to provide messaging connectivity and transport. An exemplaryconfiguration is shown in FIG. 5. Referring to FIG. 5, the EAS clients400 (e.g., applications running on the IPTV-enabled PCs) are logicallyconnected via an IP connection to the EAS server process 404.Specifically, a connection is provided between the EAS server 214 and anIM server 504. In turn, the IM server 504 is connected to a DirectoryServer 508, that also optionally functions as anauthentication/identification server. The directory server is used to,inter alia, authenticate IM clients and provide access thereto to EASdata. An IP connection is established between the IM server 504 and theIM (EAS) client application running on the client devices 220 via the IMmultiplexers 506 that multiplex/demultiplex EAS data to/from multiple IMclients and the IM server. The client devices 220 are also optionallyconnected to a web server 512 that makes IM resources available to theIM software running on the client devices.

Referring to the signal exchange diagram of FIG. 5 a, key functionalelements of the exemplary system utilizing IM infrastructure fordelivery of EAS data include: an EAS client 400, a web server 512, an IMMultiplexer 506, an IM server 504, an EAS server 214, and anauthentication/identification server 508. It will be recognized thatwhile illustrated as separate entities for clarity, more than one of theforegoing functions may be implemented on the same hardware platform incertain embodiments of the invention.

FIG. 5 a illustrates two sets of signal exchanges that occur during theoperation of the exemplary system. During clientauthentication/identification, the EAS client 400 locates the web server512 from information available to it (e.g., using electronic programguide information), and sends an EAS data viewing request 570. Theissuance of this request by the client process 400 can be structured sothat the goal of timely and unimpeded delivery and display of EAS datato valid users is in no way frustrated; e.g., by (i) causing the EASrequest 570 to be issued in response to a downstream broadcast “trigger”message issued by the EAS server 214 or other upstream entity(indicating that “flash” EAS traffic is pending delivery), (ii) causingvalid EAS clients 400 to periodically issue such requests 570 (somewhatakin to a client device “heartbeat”) during operation irrespective ofany downstream traffic, and so forth. The web server returns the addressof a IM multiplexer (muxer) 506 in a message 572. The client thenproceeds to contact the IM muxer 506 using a message 574 presenting itscredentials. The IM muxer forwards this request to the appropriate IMserver 504 in another message 576. In one embodiment, the client device220 (and EAS process 400) may be directly provided the resource locator(URL) of the IM muxer 506 or of the IM server 504, thereby making theaforementioned intermediate steps and messaging unnecessary.

The IM server 504 next performs a message exchange with theauthentication server 508. In this message exchange, the IM serverpresents the authentication server 508 with credentials of the EASclient 400 that has requested to receive EAS data per step 578, and inreturn the authentication server provides the IM server 504 informationabout the service(s) the EAS client is authorized to receive (step 580).Once the client device is authenticated (or not authenticated), anappropriate success or reject message is sent by the IM server (step582) via the IM muxer or another channel to the EAS client 400 (step584).

When the EAS client determines that it must receive EAS data, the clientdevice 220 contacts the EAS server 214. If the device 220 is notpreviously known or served, the EAS server may want to check itscredentials and service level by sending a query to the IM server 404(step 590), which in turn communicates with the authentication server508 via query (step 592) and response (step 594) mechanisms. Once thedevice 220 is authenticated, EAS data begins to flow from the EAS server(step 594) to the IM muxer (step 596) and ultimately to the EAS-capableclient device (step 598).

It will be appreciated that many of the steps illustrated within theexemplary protocol of FIG. 5 a can be obviated in favor of reducedclient device/process authentication if desired. For example, in orderto avoid situations where a client process can't authenticate, therebypreventing their receipt of the EAS data, the authentication can bewaived or eliminated. However, the presence of client processauthentication helps eliminate the ability of surreptitious attempts to“engage” the EAS server 214 or other entities within the systemarchitecture in order to effectuate a denial-of-service or similar typeof attack that could affect other IM EAS users.

Additionally, since the EAS “trigger” message may go out to many clients400 at effectively the same time (thereby triggering a surge in upstreamrequests for client process authentication), the trigger messages(and/or the EAS data requests from the clients can be staggered,buffered, or otherwise diffused in time or location to reduce the burdenon the IM/authentication server(s).

Re-use of existing Instant Messenger (IM) service infrastructure for EASmessage transmission provides a convenient way to deploy EAS in an IPTVnetwork by reusing many software components typically available on manyIPTV platforms. However, it may not be adequate to meet some governmentEAS requirements where non-EAS adapted IM client applications (i.e.,“off-the-shelf” versions of IM applications such as AOL InstantMessenger or the like) are used. For example, such non-EAS adaptedapplications may not be able to mute audio played within an IPTV videoclient unless specifically configured to do so. Similarly, the IM clientmay not be able to force re-tune a video decoder instantaneously to anEAS channel (if a video feed is available with the emergency alertmessage) unless specifically configured.

However, the present invention contemplates that these features andfunctions can be addressed by the network operator/MSO by either (i)providing a “customized” or EAS-adapted IM client with suchcapabilities, or (ii) coordinating with the IM client developers toinclude these features as part of an upgrade package to the software,both of which can be readily downloaded to the client device via the IPor other network. For example, such EAS-adapted IM client could beconfigured to generate and transmit a “retune” message to IP-enabledvideo client 400 running on the client device 220 to effectuate a retuneevent. Alternatively, the IM client application can be integrated withinthe EAS client process 400, so that IM capability is integral to the EASclient upon installation. Myriad other approaches may be used as well.

Client Protocol Stack and Emergency Video Feed Considerations—

Various aspects of the client device operation and protocol stack mustbe considered in the context of EAS data/video delivery.

In the case of a forced tune to an emergency alert video feed, severalfunctional elements of the end-to-end EAS subsystem must work incoordination with each other. Specifically, the emergency alert videoservers 214 must have sufficient availability and capability such thatvideo in multiple formats (Quicktime, Windows Media, H.264, etc.) can bestreamed appropriately to client devices.

Additionally, the client device 220 application software stack must bearranged such that the EAS client application is able to force tuning ofthe video decoder application, as well as muting the ongoing audioportion of the pre-existing content-based program, and output EAS audioin its place. In this sense, the EAS client acts somewhat like an OCAP“monitor” application for a DSTB; the EAS client must have significantcontrol over the necessary hardware/firmware/software processes in orderto effectuate these functions, such as being able to immediatelyterminate audio decoding (or at least the feed of decoded audio data tothe audio delivery hardware) in favor of the EAS audio data. FIG. 6illustrates one exemplary client device (e.g., PC) protocol stackillustrating the placement of the EAS client 400 (here, embodied toinclude a messenger application) of the present invention therein.

The EAS re-tuning message(s) must also be authenticated so that “spoof”EAS re-tuning attempts are avoided or eliminated. For example, this canbe accomplished by authenticating the message itself (hashing, digitalcertificates), authenticating the source of the message (e.g.,DomainKeys by Yahoo or by explicit request/response signal exchange asdescribed above), and/or by authenticating the IP address/port ID towhich the EAS message is requesting a re-tuning (for example, forcedre-tuning can only occur when the target comprises a fixed orpredetermined IP/port combination as pre-programmed in the EAS client).

Additionally, EAS messages are typically meant to be relevant only atthe time at which they are transmitted. It is therefore sometimesadvantageous to filter these messages out from personal video recording(PVR) or similar functions where latency (or geographic “shifting”) isintroduced. If a media program is being actively viewed and recordedsimultaneously, the EAS client 400 should be designed to preserve all ofthe desired EAS effects (i.e., audio substitution, graphical display oftext, video forced tuning) to the end user display device/process,without providing such effects for the recording device/process. Hence,in one embodiment, the recording process precedes the overlay or displayof the EAS information, thereby preventing the EAS information frombeing recorded. This functionality is typical in many existing devices,and hence does not require significant adaptation in order to implementthe present invention. In an alternate embodiment, the EAS client 400 isconfigured to identify media program streams which are being recorded(such as to a hard drive resident or in data communication with theclient device 220), and allow them to continue recording unchanged,while the viewed stream is altered as previously described. Hence, theEAS client is given the ability to differentiate between varioushardware devices and associated processes on the client device (e.g.,recording and display), and treat them in an agnostic fashion.

Personal Video Encoder (PVE) Variants—

In another embodiment of the invention, a personal video encoder (PVE)or comparable device is used as the basis for the client device 220. Forexample, the “Slingbox” device manufactured by Sling Media of San Mateo,Calif. is one such exemplary device which is capable of enabling a userto watch TV programming from various locations via an Internet-connectedPC or similar device. The device is generally connected between thesubscriber's cable/satellite video drop and DSTB, and has a TV tunerinside. The user tunes to a given channel, and the device encodes thevideo streamed over the cable/satellite in Windows Media or similarformat. The encoded content is streamed to a client application on aWindows XP-based or similar PC via an IP network such as the Internet,and hence the user can view the data locally (i.e., at the samepremises) or remotely so long as they have access to the IP distributionnetwork. Such devices, however, do not have the ability to receive,render and deliver the EAS data to the appropriate user application, orto invoke tuning to an EAS-supplied video stream. Such devices are alsonot able to substitute EAS audio data for the audio portion of acurrently streaming video program. Hence, the present inventionadvantageously extends the capability of such PVE devices by providingthe capability to receive the CC data and deliver it (e.g., in anOOB-fashion) to the Windows-based or other client application fordisplay and rendering, as well as control functions (e.g., how large thetext is when displayed, where it is displayed, language, etc.).

In one embodiment, the PVE merely acts as pass-through or router entity,with the EAS data receipt, decoding and player functions being disposedentirely on the PC or laptop computer used as the subscriber's “viewing”device at their actual location.

The EAS-enabled client on the user's PC or similar device provides theaforementioned “forced tune” functionality as well as audio portionsubstitution within the “remote” client device. In another embodiment,the PVE is outfitted with the necessary EAS data receiving and decodingsoftware, which receives the EAS data and then acts as a full-functionproxy for the remote client device (akin to the prior art “analog”approach previously described herein, except in the context of a digitalPVE environment).

Business Methods—

In another aspect of the invention, methods of doing business associatedwith the EAS data delivery capability previously disclosed herein arenow described in detail.

In one variant, these methods effectively bundle or link one or morefeatures not critical to (but ideally useful or desirable with) the EASdata delivery in order to provide subscribers enhanced functionality and“user experience.” While the provision of basic EAS data (e.g., audio,text, and/or video) to subscribers is essentially mandated by federalregulation, ancillary services or capabilities are not, and subscribersmay find these ancillary services and capabilities useful. Theseancillary services or features can comprise a basis for a multi-tieredor “premium” subscriber class business model, be given as an incentivefeature for a subscription, or otherwise.

One exemplary ancillary service that can be bundled with the EAS datadelivery comprises the ability to “pass through” EAS data orcommunications to remote entities in data communication with the base(e.g., IP) distribution network. For example, the aforementioned PVEdevice (e.g., Slingbox or similar) can be distributed under lease (orfor free) to subscribers as part of the model. The PVE device allows thesubscriber to access network programming via their mobile device (e.g.,laptop) from a remote location. It would be highly desirable for manyusers, especially those who travel frequently, to have assurance ofreceiving EAS information via their mobile or remote devices, since suchEAS communications will likely be of some import regarding thatsubscriber's home, business, family, etc. For example, a subscriber maywish to know that their residence is subject to a hurricane or tornadowarning so that they can take pre-emptive action or monitor thesituation more closely. This also would relieve them of the requirementof monitoring conventional information channels such as TV news or radioin their current (remote) area in order to glean information regardingthe location of their residence, etc. Hence, the system could become a“remote first warning” mechanism for the subscriber, irrespective oftheir location. Only connectivity to the bearer (e.g., IP) network wouldbe required in order to utilize this feature.

Another such ancillary service could comprise providing topicallyrelated or coupled information sources, such as e.g., direct orreal-time Doppler radar feeds from NWS or similar entities in the localregion in the case of an EAS tornado alert message, or NWS satellite orradar imaging for an impending hurricane. These ancillary sources coulddirectly coupled to the EAS data delivery, such as where the videostream/feed to which the EAS client 400 tunes includes this informationalong with or in place of the less-descriptive federally mandatedinformation. For example, in one variant, a multi-pane displaycomprising, e.g., (i) the federally mandated alert message or data, (ii)local evacuation route/traffic information, (iii) Doppler/satelliteimaging, and (iv) real-time “incident” reporting (somewhat akin toreal-time traffic incident reporting “blogs” currently maintained byCalifornia DOT/Highway Patrol) could be provided to subscribers in orderto provide them multi-source data fusion when it is most needed (i.e.,at the time of report). This also obviates the subscriber having to huntfor this information, such as by channel hopping, thereby wastingpotentially precious time. This can also be coupled to theaforementioned PVE capability if desired, thereby providing the userwith a mobile source of fused data (e.g., via a WiFi or WiMax node,cellular interface, satellite link, or other mobile communicationslink).

The methods and apparatus of co-pending and co-owned U.S. patentapplication Ser. No. 11/198,620 filed Aug. 4, 2005 and entitled “METHODAND APPARATUS FOR CONTEXT-SPECIFIC CONTENT DELIVERY”, which isincorporated herein by reference in its entirety may also be utilized inconjunction with the present invention. Specifically, the aforementionedapplication discloses, inter alia, methods and apparatus for utilizingmetadata or similar data structures associated with video content as abasis for providing targeted and seamless linking to a secondary contentsource (e.g., advertising server links) within a video player windowdisplayed on a PC or similar device. Accordingly, the secondary contentsources could be constrained in one embodiment to include those ofparticular relevance to certain emergency situations. For example, inthe case of an EAS message or video feed relating to a tornado, thedata/feed could be embedded or associated with metadata (e.g., XMLformatted “tornado”) that could be used as the basis of accessingcontent sources (web sites, local files, third party servers, etc.) thatare particularly relevant to and/or useful for tornados, such as the NWStornado watch site, the local traffic report website, etc. Hence, theuser views the relevant EAS content and then is immediately presentedwith a group of relevant links for further information.

It will also be recognized that due to substantial similarities, themethods and apparatus for caption data (closed captioning) deliverydescribed in co-owned and co-pending U.S. patent application Ser. No.11/298,247 filed contemporaneously herewith and entitled “CAPTION DATADELIVERY APPARATUS AND METHODS”, previously incorporated herein, can bereadily used in conjunction with the EAS data delivery apparatus andmethods described herein. For example, a common EAS and CC server entitycan be specified at the head-end 150 or another node to permit the EASand CC functions to be integrated. Furthermore, the EAS clientapplication can include CC functionality (or vice versa), which may alsoinclude the ability to support one or more commercial video decoders(such as Real, H.264, WMP, etc.) as well as IM capability.

It will also be recognized that one or more existing softwareapplications can be used with the present invention to provide theprimary functionality of that application in an “EAS-enabled” fashion.For example, in one exemplary embodiment, the Yahoo! Messengerapplication is used to provide streaming IP media delivery (e.g., chat,audio, video, etc.) that is also enabled for EAS delivery. Myriad othervariants of this basic idea will also be recognized by those of ordinaryskill provided the present disclosure.

It will be recognized that while certain aspects of the invention aredescribed in terms of a specific sequence of steps of a method, thesedescriptions are only illustrative of the broader methods of theinvention, and may be modified as required by the particularapplication. Certain steps may be rendered unnecessary or optional undercertain circumstances. Additionally, certain steps or functionality maybe added to the disclosed embodiments, or the order of performance oftwo or more steps permuted. All such variations are considered to beencompassed within the invention disclosed and claimed herein.

While the above detailed description has shown, described, and pointedout novel features of the invention as applied to various embodiments,it will be understood that various omissions, substitutions, and changesin the form and details of the device or process illustrated may be madeby those skilled in the art without departing from the invention. Theforegoing description is of the best mode presently contemplated ofcarrying out the invention. This description is in no way meant to belimiting, but rather should be taken as illustrative of the generalprinciples of the invention. The scope of the invention should bedetermined with reference to the claims.

1. In a content-based network having a server and a client device indata communication therewith, a method of providing primary content,emergency-related secondary content, and contextually-related tertiarycontent to users of said network, said method comprising: deliveringsaid primary content to said client device; delivering said secondarycontent to said client device; accessing a descriptive data fileassociated with said secondary content in order to obtain descriptivedata therefrom, said descriptive data relating to at least one aspect ofsaid emergency-related content; providing said descriptive data to aprocessing entity to identify contextually related tertiary content;transmitting said secondary and tertiary content to said client deviceover said network; and selectively displaying said primary content andat least one of said secondary and tertiary content on a display deviceassociated with said client device.
 2. The method of claim 1, whereinsaid act of displaying comprises displaying said secondary and tertiarycontent in a common display window generated by a software applicationadapted for playing audiovisual content.
 3. The method of claim 2,wherein: said act of displaying further comprises displaying saidtertiary content immediately following the completion of the display ofsaid secondary content; and said tertiary content comprisessubstantially textual links to other information.
 4. The method of claim1, wherein said contextually-related tertiary content comprisesadditional information generated from sources other than a source ofsaid emergency-related secondary content.
 5. In a content-based networkhaving a server and a client device in data communication therewith, amethod of providing primary content, emergency-related secondarycontent, and contextually-related tertiary content to users of saidnetwork, said method comprising: delivering said primary content to saidclient device; delivering said secondary content to said client device;accessing a descriptive data file associated with said secondary contentin order to obtain descriptive data therefrom, said descriptive datarelating to at least one aspect of said emergency-related content;providing said descriptive data to a processing entity to identifycontextually related tertiary content comprising substantially textuallinks to other information; transmitting said secondary and tertiarycontent to said client device over said network; and selectivelydisplaying said primary content and said secondary and tertiary contenton a display device associated with said client device, said displayingcomprising: displaying said secondary and tertiary content in a commondisplay window generated by a software application adapted for playingaudiovisual content; and displaying said tertiary content immediatelyfollowing the completion of the display of said secondary content. 6.The method of claim 5, wherein said content-based network comprises anInternet Protocol Television (IPTV) network.
 7. The method of claim 5,wherein said content-based network comprises at least portions of an HFCcable network including at least one cable modem interposed between saidserver and said client device.
 8. The method of claim 5, wherein saidemergency-related secondary content comprises video, text, and audiocontent, and said method further comprises selectively transmittingvideo content via a packet stream different than a packet streamcarrying said audio and/or text content.
 9. The method of claim 5,further comprising generating a message causing said client device toforcibly tune to a designated program stream to receive at least aportion of said emergency-related secondary content.
 10. The method ofclaim 5, further comprising authenticating said client device prior tosaid delivering of said primary, secondary or tertiary content thereto.11. The method of claim 5, wherein said textual links to otherinformation comprise textual links to at least one of: trafficinformation; reporting information; and imaging information.
 12. In acontent-based network having a server and a client device in datacommunication therewith, a method of content to users of said network,said method comprising: accessing a data file comprising at least oneaspect of emergency-related content; identifying, based at least in parton said at least one aspect, second content related to the context ofsaid emergency-related content, said second content comprisingsubstantially textual links to other information; transmitting saidemergency-related content and said second content to said client deviceover said network; and selectively displaying said emergency-related andsaid second content on a display device associated with said clientdevice, said act of displaying comprising displaying saidemergency-related and said second content in a common display windowgenerated by a software application adapted for playing audiovisualcontent, said display of said second content immediately following thecompletion of said display of said emergency-related content.
 13. Themethod of claim 12, wherein said server is adapted to deliver saidemergency-related content, and comprises at least one of: a videostreaming server; and an emergency alert server.
 14. The method of claim12, wherein said act of transmitting said emergency-related contentfurther comprises formatting one or more emergency alerts into saidemergency-related content having a format suitable for transport oversaid network.
 15. The method of claim 14, wherein said formattingcomprises creating multiple packet formats for the same data, saidpacket formats being selected to meet one or more requirementsassociated with a plurality of client devices.
 16. The method of claim12, wherein: said server comprises a multimedia server configured tosend multimedia programs; and said act of transmitting further comprisespresenting an audio portion of said emergency-related content in placeof the audio of at least one of said multimedia programs.
 17. The methodof claim 12, wherein said server comprises a multimedia serverconfigured to send multimedia programs, and wherein said method furthercomprises: delivering said one or more multimedia programs to saidclient device over a first transport stream associated with a firstprocess running on said client device; and delivering saidemergency-related content to said client device over a second transportstream different from said first transport stream and associated with asecond process running on said client device.
 18. A client device of acontent-based network in communication with at least one server, saidclient device comprising: a receiver adapted to receive primary content,emergency-related secondary content, and tertiary content, said tertiarycontent comprising substantially textual links to other information,said other information being related to at least one aspect of saidemergency-related secondary content; and at least one display deviceadapted to display said primary content, said secondary content and saidtertiary content, said display of said secondary and tertiary contentoccurring in a common display window generated by a software applicationadapted for playing audiovisual content and said display of saidtertiary content immediately following completion of said display ofsaid secondary content.
 19. The client device of claim 18, wherein saidat least one display device is associated with a video playerapplication configured to display at least a portion of said primarycontent, and a messaging client application configured to display atleast a portion of said emergency-related secondary content.
 20. Theclient device of claim 18, wherein said at least one display device isassociated with at least one computer program configured to receive saidemergency-related secondary content, said computer program comprising aninstant messaging program.
 21. An apparatus capable of selectivelyproviding primary content, emergency-related secondary content, andcontextually-related tertiary content to a plurality of client devicesreceiving content transmitted over a packet-switched network, theapparatus comprising: a transmitter adapted to deliver said primarycontent and said emergency-related secondary content to individual onesof said plurality of client devices; and a processor adapted to run atleast one computer program thereon, said computer program configured to:access a descriptive data file associated with said emergency-relatedsecondary content in order to obtain descriptive data therefrom, saiddescriptive data relating to at least one aspect of saidemergency-related secondary content; identify said contextually-relatedtertiary content; and cause said transmitter to transmit saidcontextually-related tertiary content to said individual ones of saidplurality of client devices for display thereon.
 22. The apparatus ofclaim 21, wherein said transmission of said primary content, saidemergency-related secondary content, and said contextually-relatedtertiary content is based at least in part on information identifyingthe location of cable modem units associated with respective ones ofsaid plurality of client devices.
 23. The apparatus of claim 21, whereinsaid apparatus is configured to generate a message to one or more ofsaid plurality of client devices causing said one or more client devicesto forcibly tune to a designated program stream to receive at least aportion of said emergency-related secondary content.
 24. The apparatusof claim 21, wherein said computer program is further configured toselectively provide services to respective ones of said plurality ofclient devices, said services comprising services which are related tothe context of said emergency-related secondary content.
 25. Theapparatus of claim 21, wherein said contextually-related tertiarycontent comprises at least one of: evacuation route or trafficinformation; Doppler or satellite imaging; and real-time reportinginformation.
 26. In a content-based network having a server and a clientdevice in data communication therewith, a method of providing primarycontent, emergency-related secondary content, and contextually-relatedtertiary content to users of said network, said method comprising:delivering said primary content to said client device; delivering saidsecondary content to said client device; accessing a descriptive datafile associated with said secondary content in order to obtaindescriptive data therefrom, said descriptive data relating to at leastone aspect of said emergency-related content; providing said descriptivedata to a processing entity to identify contextually related tertiarycontent; transmitting said secondary and tertiary content to said clientdevice over said network; selectively displaying said primary content,secondary content, and tertiary content on a display device associatedwith said client device.